Polarized telephone signal-bell.



- E. E. YAXLEY.

POLARIZED TELEPHONE SIGNAL BELL.

APPLICATION FILED MAR. 13, 1901; F0 MODEL.

PATENTED JAN". 1a, 1903.-

UNITED STATES PATENT OFFICE.

ERNEST E. YAXLEY, OF CHICAGO, ILLINOIS, ASSIGNOR TO AMERICAN ELECTRICTELEPHONE COMPANY, OF CHICAGO, ILLINOIS, A CORPO- RATION OF NEYV JERSEY.

POLARIZED TELEPHONE SIGNAL-BELL.

SPECIFICATION formmgpart of Letters Patent No. 718,235, dated January13, 1903. Application filed March 13, 190i. Se ialNO. 50,967. (Nomodel-1 T0 ctZZ whom, it 777/Cby concern.-

Be it known that I, ERNEST E. YAXLEY, a citizen of the United States ofAmerica, and a resident of Chicago, Cook county, Illinois, have inventeda certain new and useful Improvement in Polarized Telephone Signal-Bells, of which the following is a specification.

In telephone systems, usually at subscribers stations, an audiblesignaling device, usually a polarized bell,'is employed to give a signalwhereby to call the subscriber to the telephone. This apparatuscomprises a frame, a pair of electromagnets, a permanent magnet, anarmature upon which the electromagnets and permanent magnet act, and abell striker-lever operated by the armature to strike the gongs of thebell.

My invention relates to certain structural details of improvement in apolarized bell of this character, and has for its object the provisionof means whereby the adjustment of the armature to determine its properstroke or movement may be effected with facility and accuracy, so thatthe gong-striker may be adjusted to the proper stroke with accuracy, andto provide a construction which shall render the apparatus moresubstantial and less liable to get out of adjustment.

Reference may now be had to the accompanying drawings, in which- Figure1 is a side elevation of the improved polarized electromagnetic ringeror bell apparatus. Fig. 2 is a view of the under side of the yoke andplan view of the armature, and Fig. 3 is a front elevation of theimproved electric bell apparatus shown in Fig. 1.

The electric bell consists of a frame composed of the plate A, the bars,posts, or standards B B, and the yoke D. The permanent magnetEisconnected,asusual,to the connecting-plate A and extended downwardlyuntil its lower end is below the armature H. This armature H is pivotedin the downturned ears H and the striker H attached to said armature,projects upwardly through an enlarged orifice H in the yoke. Theelectromagnets J J are held in place by means of the frame, and thelower ends of the cores J J of said electromagnets project through andare held within the yoke D. These cores by so projecting through andbeyond the plane of the yoke are brought into a position to act upon thearmature H, which is positioned beyond the said yoke D. The bell-strikerH is placed between and operates upon the gongs Kin the usual manner.

From the foregoing description it will be observed that the armature ispositioned beyond the yoke D of the frame instead of be ing between theyoke and the electromagnets, as is usually the case. Passing the ends ofthe coresthrough the yoke and to a point beyond the plane of said yokebrings them into inductive proximity with relation to the armature. Bythus disposing the armature it is possible to adjust the stroke orvibratory movement of the same with facility and accuracy, and thusobtain an accurate movement or vibration of the striker with relation tothe gongs. Further, by passing the cores J of the electromagnets Jthrough the yoke D a more substantial and solid structure is therebyobtained, which is less liable to get out of adjustment when locked inplace by means of the nuts L on the connecting-bars B. This is evident,as the cores are firmly held in place at their lower ends instead ofbeing permitted to remain unsecured, as is usually the case, and,further, the said cores are brought by being thus projected beyond theplane of the yoke into inductive proximity to the armature H, which ispositioned beyond said yoke. In this construction the permanent magnet,as E, is not used in any way for varying or adjusting the armature. Avery bad feature of construction is thus avoided, owing to the liabilityin construction where it is so employed of the hardened-steel magnets tobecome broken,due to the strain thrown upon them by the adjusting-screwsor other means. In this device the adjusting is accomplished through thenuts L L on the posts or rods B.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. A polarized bell comprising a permanent magnet, a pair ofelectromagnets having projecting cores, a yoke through which said coresproject, adjusting devices for causing a bodily movement of said yokeupon said cores,

an armature pivoted upon and outside of said yoke, a pair of gongs, anda striker mounted to vibrate With said armature.

2. The combination of a gong, a pair of electromagnets having projectingcores, a yoke through which said cores project, an armature pivoted uponand arranged outside of said yoke, a permanent magnet having one polefree and the other secured to the said cores, a striker mounted tovibrate with said armature, and adjusting devices independent of saidmagnets for adjusting said yoke.

3. The combination of the plate formed with a recess at its middle, thetwo electromagnets secured to the middle portion of said plate, thepermanent magnet having one pole free and the other secured in saidrecess, a yoke through which the cores of said magnets project, anarmature pivoted upon and outside of said yoke, screw-threaded membersapplied to the ends of said yoke and adapted for adjusting the latterbodily along the said cores, one or more gongs, and a striker mounted tovibrate with said armature.

4. In a polarized bell, the combination of a pair of electromagnets, apermanent magnet having one pole fixed and the other free, a

yoke having openings through which the cores of said electromagnetsproject, an armature pivoted upon the yoke between the latter and thefree pole of said permanent magnet, suitable screw-threaded members foradjusting the yoke bodily along said cores, one or more gongs, and astriker mounted to Vibrate the said armature.

5. A polarized electric bell, comprising a pair of electromagnets havingprojecting cores, a permanent magnet, adjustable screwthreaded memberssupported at opposite sides of said electromagnets, a yoke having itsopposite ends supported by the said screwthreaded members, said yokethus supported for bodily adjustment being provided with openingsadapted to receive the projecting end portions of the said cores, anarmature pivoted on the yoke and located between the ends of said coresand one pole of said permanent magnet, a gong, and a striker mounted onsaid armature and projecting through said yoke.

ERNEST E. YAXLEY. Witnesses:

CHARLES C. BULKLEY, HARRY P. BAUMGARTNER.

